Flyboy Dave
Posts: 13452
Joined: 3/20/2002
From: San Bernardino County,
CA, USA
Status: offline
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Cyberwolf....
....I'm glad a real mechanic finally showed up, thank you....have a look at some of the statements
Sport_pilot has made in the thread, and see what you think.
I'll be back shortly....with a wheel barrow and a shovel....no, two shovels. 
Quotes:
You can't glaze the cylinder wall with a sloppy rich setting in a glow engine. You would have to
run it lean to carbonize the castor oil. The opposite may be true with a full scale gasoline engine.
That is not glaze. It takes considerable more carbon to glaze a cylinder wall. Carbon in the ring is good.
Synthetic oil will not carbonize and castor will only carbonize when run hot or lean. Manufactures
often recommend that ringed engines run so rich that they four cycle, they will not glaze in this
conditions.
Glazing is not a good thing, at least not if too early. The carbon fills the pores and crosshatching
of the bore and this leaves a mirror surface which is too slick for the rings to seat in. I think its
ok if it happens well after the rings seat.
I am not sure how the high load prevents glazing, I think this is again from full scale, where
high loads expand the rings which helps prevent oil from working into the upper cylinder. Its
the cooling and washing effect of the rich mixture which prevents glazing in our engines.
Synthetic oil vaporizes before it actually burns. Still I suppose it could leave small amounts
of carbon, but the fact that it leaves the engine so clean tells me that there is little carbon
from synthetic oil, I suspect we get more carbon from the methanol which normally is not
enough to accumulate.
I could be wrong, but I believe that the carbon that causes glazing happens at a much smaller
scale, possibly molecular, for the ring to be very effective at scraping any immediate carbon
deposit off. Glaze is very hard and obviously well bonded to the metal under it. It also more
or less proves that carbon is actually a metal.
Well if you and I and Tower Hobby Services has never seen a glazed glow engine, how can
we be sure such a thing exists?
Those engines get a lot hotter and the oil has more oil, and because they are not four stroke
the cylinder doesn't get washed with new oil and fuel each stroke.
To date no one has shown a glazed two stroke glow engine. In fact some one who sees
hundreds of used engines sent in for repair each day stated they never saw one and explained
why it doesn't happen.
And just for record a piston ring is never truely round, even one that you have fitted and tested
by checking that light does not pass. That is why that engine needed the diamond honing. Its an
old trick used eons ago by some model racers as well.
You may be right Ed, some may be thinking of castor varnish. I consider glazing the mirror
finish walls which are created from microscopic carbon bonding to the metal. It is very hard,
probably harder than the base metal. As you know diamonds are 100% carbon, and will burn
like coal.
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I'll run down to the bakery as well....this definitely takes the cake !! 
FBD.
_____________________________
An engineer says.... "That won''t work".
A mechanic says..."Oh yeah, watch this".
"Old Age, and Treachery will overcome youth and skill".
Revver Bro #4.
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All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Glow Engines >> RE: Ringed vs Non-ringed 
RE: Ringed vs Non-ringed - 
